The present invention relates to an article of footwear, and in particular to a sole of the article of footwear with vertical grooves.
Articles of footwear with grooves have been previously proposed. Hudson (U.S. Pat. No. 6,108,943) teaches an article of footwear with a sole that includes a medial outsole element with a plurality of flex grooves. The grooves are oriented to mimic the direction of many movements made in tennis. Hudson teaches that traction strips can be molded into some or all of the flex grooves. Hudson fails to teach provisions for providing torsion in an article. There is a need in the art for a design that overcomes these shortcomings.